I am using Ruby on Rails 3.0.7 and I would like to learn to write "advanced" plugins for the current versione of the framework. In order to do that I would like to buy some books but what I have seen on the Amazon website are two or three year old...

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3 Answers
3

If you're using Rails 3.0.7 I highly recommend against any books that are "two or three years old."

Edge RailsGuides contain the latest official guides for Ruby on Rails. You should check out the Extending Rails section.

Edit:
You should also be aware that Rails 3.x plugins are mostly gems now as the original plugin system basically inserted the plugin directly into your codebase. Gems are much more extensible and don't muck up your codebase.

You should take a look at some popular Rails 3.x extensions out there: